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An Observational Study of the 30-50 Day Atmospheric Oscillations Part I: Structure and Propagation 被引量:20
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作者 李崇银 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第3期294-304,共11页
Features of structure and propagation of the 30 to SO day atmospheric oscillations are investigated using the ECMWF analysis of 1980-1983. Evidence is provided to confirm the characteristics of the oscillation in the ... Features of structure and propagation of the 30 to SO day atmospheric oscillations are investigated using the ECMWF analysis of 1980-1983. Evidence is provided to confirm the characteristics of the oscillation in the equatorial region. Those in the mid-high latitudes, however, are revealed to be very different from the tropics and pose a strong barotropic structure. Horizontal coherence shows teleconnection patterns which can be identified as EAP and PNA. The wind field of the specified time scale of the oscillation appears as long-lived vortices and vortex pairs. Mid-latitude perturbations propagate clearly westwards, especially during the winter season. In the high latitudes, they propagate westwards in the winter but eastwards in the summer. Meridional propagations are rather different from region to region. 展开更多
关键词 An Observational study of the 30-50 Day Atmospheric Oscillations Part I HIGH
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Potential Toxicological and Cardiopulmonary Effects of PM2,5 Exposure and Related Mortality:Findings of Recent Studies Published during 2003-2013 被引量:16
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作者 Mohammed O.A.Mohammed SONG Wei Wei +7 位作者 MA Wan Li LI Wen Long LI Yi Fan Afed Ullah Khan Mohammed A.E.M.Ibrahim Osman Adam Maarouf Alshebli A Ahmed John J.Ambuchi 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第1期66-79,共14页
Air pollution has environmental issue owing become a serious to its diverse harmful effects on the physical and biological environment. According to the Environmental Protection Agency (EPA) and the World Health Org... Air pollution has environmental issue owing become a serious to its diverse harmful effects on the physical and biological environment. According to the Environmental Protection Agency (EPA) and the World Health Organization (WHO), air pollution affects millions of people worldwide. Hundreds of thousands of deaths each year and a range of diseases, particularly among vulnerable groups (i.e., children, the elderly, and people with special medical conditions), are attributed to air pollution. These effects are not always caused by single pollutant in the air; rather, they are considered consequences of the multi-pollutants to which people are simultaneously exposed. 展开更多
关键词 Potential Toxicological and Cardiopulmonary Effects of PM lung Exposure and Related Mortality Findings of Recent Studies Published during 2003-2013 2003
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Numerical study on three-dimensional flow field of continuously rotating detonation in a toroidal chamber 被引量:4
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作者 Xu-Dong Zhang Bao-Chun Fan +2 位作者 Ming-Yue Gui Zhen-Hua Pan Gang Dong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第1期66-72,共7页
Gaseous detonation propagating in a toroidal chamber was numerically studied for hydrogen/oxygen/nitrogen mixtures. The numerical method used is based on the three-dimensional Euler equations with detailed finiterate ... Gaseous detonation propagating in a toroidal chamber was numerically studied for hydrogen/oxygen/nitrogen mixtures. The numerical method used is based on the three-dimensional Euler equations with detailed finiterate chemistry. The results show that the calculated streak picture is in qualitative agreement with the picture recorded by a high speed streak camera from published literature. The three-dimensional flow field induced by a continuously rotating detonation was visualized and distinctive features of the rotating detonations were clearly depicted. Owing to the unconfined character of detonation wavelet, a deficit of detonation parameters was observed. Due to the effects of wall geometries, the strength of the outside detonation front is stronger than that of the inside portion. The detonation thus propagates with a constant circular velocity. Numerical simulation also shows three-dimensional rotating detonation structures, which display specific feature of the detonation- shock combined wave. Discrete burning gas pockets are formed due to instability of the discontinuity. It is believed that the present study could give an insight into the interest- ing properties of the continuously rotating detonation, and is thus beneficial to the design of continuous detonation propulsion systems. 展开更多
关键词 Continuously rotating detonation - Three- dimensional flow field structure - Numerical study Detonation parameters deficit ~ Effects of wall geometries
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An Observational Study of the 30-50 Day Atmospheric Oscillations Part II: Temporal Evolution and Hemispheric Interaction across the Equator 被引量:3
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作者 李崇银 周亚萍 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第4期399-406,共8页
In this part, the temporal evolution and interaction across the equator of 30-50 day oscillation in the atmosphere are investigated further. The annual variation of 30-50 day oscillation is quite obvious in the mid-hi... In this part, the temporal evolution and interaction across the equator of 30-50 day oscillation in the atmosphere are investigated further. The annual variation of 30-50 day oscillation is quite obvious in the mid-high latitudes. In the tropical atmosphere, the obvious interannual variation is an important property for temporal evolution of 30-50 day oscillation. The low-frequency wavetrain across the equator over the central Pacific and central Atlantic area, the movement of the long-lived low-frequency system across the equator and the meridional wind component across the equator will obviously show the interaction of 30-50 day oscillation in the atmosphere across the equator. 展开更多
关键词 EI over An Observational study of the 30-50 Day Atmospheric Oscillations Part II Temporal Evolution and Hemispheric Interaction across the Equator Nino
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Experimental Study on Momentum Transfer of Surface Texture in Taylor-Couette Flow 被引量:1
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作者 Yabo XUE Zhenqiang YAO De CHENG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期754-761,共8页
The behavior of Taylor-Couette (TC) flow has been extensively studied. However, no suitable torque prediction models exist for high-capacity fluid machinery. The Eckhardt-Grossmann-Lohse (EGL) theory, derived base... The behavior of Taylor-Couette (TC) flow has been extensively studied. However, no suitable torque prediction models exist for high-capacity fluid machinery. The Eckhardt-Grossmann-Lohse (EGL) theory, derived based on the Navier-Stokes equations, is proposed to model torque behavior. This are the significant energy theory suggests that surfaces transfer interfaces between cylinders and annular flow. This study mainly focuses on the effects of surface texture on momentum transfer behavior through global torque measurement. First, a power-law torque behavior model is built to reveal the relationship between dimensionless torque and the Taylor number based on the EGL theory. Second, TC flow appa- ratus is designed and built based on the CNC machine tool to verify the torque behavior model. Third, four surface texture films are tested to check the effects of surface texture on momentum transfer. A stereo microscope and three-dimensional topography instrument are employed to analyze surface morphology. Global torque behavior is measured by rotating a multi component dynamometer, and the effects of surface texture on the annular flow behavior are observed via images obtained using a high-speed camera. Finally, torque behaviors under four differentsurface conditions are fitted and compared. The experi- mental results indicate that surface textures have a remarkable influence on torque behavior, and that the peak roughness of surface texture enhances the momentum transfer by strengthening the fluctuation in the TC flow. 展开更多
关键词 Torque behavior - Momentum transferbehavior Surface texture Experimental study TaylorCouette flow (TC flow)
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Preparation and spectroscopic, and thermal decomposition kinetic studies of europium(Ⅲ) complex [Eu(HNBD)_3] (HNBD: 1-(6-hydroxy-1-naphthyl)-1,3-butanedione)
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作者 WANG Dunjia ZHENG Chunyang SUN Tingquan 《Rare Metals》 SCIE EI CAS CSCD 2007年第4期335-341,共7页
The complex of Eu(IH) with 1-(6-hydroxy- 1-naphthyl)- 1,3-butanedione (HNBD) was prepared for the first time and characterized by elemental analysis, IR, UV, fluorescence spectrum, and DTA-TG-DTG techniques. The... The complex of Eu(IH) with 1-(6-hydroxy- 1-naphthyl)- 1,3-butanedione (HNBD) was prepared for the first time and characterized by elemental analysis, IR, UV, fluorescence spectrum, and DTA-TG-DTG techniques. The IR and UV-visible spectra showed that Eu(Ⅲ) ion was coordinated to the HNBD ligand. The fluorescence spectrum showed the presence of Eu^3+ characteristic emission. The TG-DTA-DTG curves showed that the thermal decomposition of the anhydrous complex was a two-stage process and the final residue was Eu2O3. The thermal decomposition kinetic parameters of the complex were evaluated from TG-DTG data by using three kinds of integral methods (Coat-Redfem equation, Horowitz and Metzger equation, Madhusudanan-Krishnan-Ninan equation). The kinetic parameters of the first stage are E^* = 164.02 kJ.moll, A = 1.31 × 10^15 s^-l, AS^*= 42.27 J·K^-l·mol^-l, △H^* = 159.51 kJ·mol^-l, △G^*= 136.54 kJ·mol^-l, and n = 3.1, those of the second stage are E^*= 128.52 kJ·mol^-l, A = 1.44× 106 s^-1, △S^*= - 136.89 J·K^-l·mol^-l, △H^* = 120.41 kJ·mol^-l, △G^*= 283.85 kJ·mol^-l, and n = 1.1. 展开更多
关键词 physical chemistry thermal decomposition kinetics spectroscopic studies Eu(Ⅲ) complex 1-(6-hydroxy-1-naphthyl)- 1 3-butanedione
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Decay Study of the Neutron-Rich Nucleus ^(175)Er
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作者 Zhang Xueqian Yuan Shuanggui Yang Weifan Mou Wantong Li Zongwei Luo Yixiao Zhong Jiquan Institute of Modern Physics,the Chinese Academy of Sciences,Lanzhou 730000 《Chinese journal of nuclear physics》 1997年第1期16-22,共7页
The decay of the neutron-rich erbium isotope <sup>175</sup>Er is studied by using the reaction<sup>176</sup>Yb(n,2p)<sup>175</sup>Er.A partial decay scheme is proposed on the basi... The decay of the neutron-rich erbium isotope <sup>175</sup>Er is studied by using the reaction<sup>176</sup>Yb(n,2p)<sup>175</sup>Er.A partial decay scheme is proposed on the basis of X-γ and γ-γ coincidencemeasurements,taking into account eight observed gamma rays.A ground rotational band is as-signed to <sup>175</sup>Tm.Some systematic behaviors of 1/2+[411] ground rotational bands in odd-Athulium are described.The experimental and calculated decoupling parameters of these bandsare compared. 展开更多
关键词 DECAY study X-γ and γ-γ COINCIDENCE GROUND ROTATIONAL BAND Systematic behavior
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缺氧诱导因子-1α和BCL-2/腺病毒E1B19 kDa相关蛋白3在中耳胆脂瘤表达及意义 被引量:1
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作者 岑瑞祥 赵凯 +4 位作者 万浪 彭聪 曹炜 刘原宙 龚国清 《中国耳鼻咽喉头颈外科》 CSCD 2019年第11期621-623,共3页
目的探讨缺氧诱导因子-1α(hypoxia inducible factor-1,HIF-1α)和BCL-2/腺病毒E1B19KDa相关蛋白3(Bcl2/adenovirus E1B 19 kD interacting protein 3,BNIP3)在中耳胆脂瘤中的表达及胆脂瘤上皮的凋亡情况。方法采用免疫组织化学方法检... 目的探讨缺氧诱导因子-1α(hypoxia inducible factor-1,HIF-1α)和BCL-2/腺病毒E1B19KDa相关蛋白3(Bcl2/adenovirus E1B 19 kD interacting protein 3,BNIP3)在中耳胆脂瘤中的表达及胆脂瘤上皮的凋亡情况。方法采用免疫组织化学方法检测30例中耳胆脂瘤标本与18例外耳道皮肤标本中HIF-1α和BNIP3蛋白的表达情况,使用末端脱氧核苷酸转移酶介导的dUTP缺口末端标记(terminal deoxynucleotidyl transferase-mediated dUTP nick-end-labeling,Tunel)检测20例中耳胆脂瘤标本和18例外耳道皮肤标本的凋亡情况。使用Pearson相关分析检验HIF-1α和BNIP3蛋白之间的相关性。结果 HIF-1α在胆脂瘤组和对照组的平均光密度分别为0.16±0.07和0.08±0.03,两组比较差异有统计学意义(t=4.279,P<0.01);BNIP3在胆脂瘤组和对照组的平均光密度分别为0.16±0.08和0.11±0.06,两组比较差异有统计学意义(t=2.463,P=0.0185);经pearson相关分析,在胆脂瘤上皮中,HIF-1α和BNIP3之间呈正相关(r=0.418,P=0.003);Tunel染色中,凋亡指数在胆脂瘤组和对照组分别为(52.8±12.5)%和(9.99±2.97)%,两组比较差异有统计学意义(t=14.166,P<0.01)。结论 HIF-1α和BNIP3在中耳胆脂瘤中的异常表达可能与胆脂瘤的高凋亡特性有关。 展开更多
关键词 胆脂瘤 中耳(Cholesteatoma Middle Ear) 对比研究(Comparative study) 细胞凋亡(Apoptosis) 缺氧诱导因子-1α(hypoxia-inducible factor-1α) BCL-2/腺病毒E1B19 kDa相关蛋白3(Bcl2/adenovirus E1B 19 kD interacting protein 3)
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Multi-train modeling and simulation integrated with traction power supply solver using simplified Newton–Raphson method 被引量:5
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作者 Thanatchai Kulworawanichpong 《Journal of Modern Transportation》 2015年第4期241-251,共11页
Multi-train modeling and simulation plays a vital role in railway electrification during operation and planning phase. Study of peak power demand and energy consumed by each traction substation needs to be deter- mine... Multi-train modeling and simulation plays a vital role in railway electrification during operation and planning phase. Study of peak power demand and energy consumed by each traction substation needs to be deter- mined to verify that electrical energy flowing in its railway power feeding system is appropriate or not. Gauss-Seidel, conventional Newton-Raphson, and current injection methods are well-known and widely accepted as a tool for electrical power network solver in DC railway power supply study. In this paper, a simplified Newton-Raphson method has been proposed. The proposed method employs a set of current-balance equations at each electrical node instead of the conventional power-balance equation used in the conventional Newton-Raphson method. This concept can remarkably reduce execution time and computing complexity for multi-train simulation. To evaluate its use, Sukhumvit line of Bangkok transit system (BTS) of Thai- land with 21.6-km line length and 22 passenger stopping stations is set as a test system. The multi-train simulation integrated with the proposed power network solver is developed to simulate 1-h operation service of selected 5-min headway. From the obtained results, the proposed method is more efficient with approximately 18 % faster than the conventional Newton-Raphson method and just over 6 % faster than the current injection method. 展开更多
关键词 Newton-Raphson method Gauss-Seidelmethod - Current-balance equation Current injectionmethod Multi-train simulation Power supply study
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Comparative study of HFACS and the 24Model accident causation models 被引量:5
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作者 Gui Fu Jia-Lin Cao +1 位作者 Lin Zhou Yuan-Chi Xiang 《Petroleum Science》 SCIE CAS CSCD 2017年第3期570-578,共9页
A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system(HFACS) and the accident causation "2-4" model(2... A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system(HFACS) and the accident causation "2-4" model(24 Model), as well as to provide a reference for safety researchers and accident investigators to select an appropriate accident analysis method. The two models are compared in terms of their theoretical foundations, cause classifications, accident analysis processes, application ranges, and accident prevention strategies. A coal and gas outburst accident is then analyzed using both models, and the application results are compared. This study shows that both the 24 Model and HFACS have strong theoretical foundations, and they can each be applied in various domains. In addition, the cause classification in HFACS is more practical, and its accident analysis process is more convenient. On the other hand, the 24 Model includes external factors, which makes the cause analysis more systematic and comprehensive. Moreover, the 24 Model puts forward more corresponding measures to prevent accidents. 展开更多
关键词 HFACS Accident causation "2-4" model Comparative study Unsafe acts External causes Coaland gas outburst accident
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TaNRT2.1-6B is a dual-affinity nitrate transporter contributing to nitrogen uptake in bread wheat under both nitrogen deficiency and sufficiency 被引量:2
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作者 Mengjiao Li Tian Wang +4 位作者 Hui Zhang Shuo Liu Wenhu Li Salah F.Abou Elwafa Hui Tian 《The Crop Journal》 SCIE CSCD 2022年第4期993-1005,共13页
Multiple nitrate transporter(NRT)genes exist in the genome of bread wheat,and it is of great importance to identify the elite NRT genes for N-efficient wheat cultivar breeding.A candidate gene association study(CGAS)o... Multiple nitrate transporter(NRT)genes exist in the genome of bread wheat,and it is of great importance to identify the elite NRT genes for N-efficient wheat cultivar breeding.A candidate gene association study(CGAS)of six N use efficiency(NUE)related traits(grain N concentration(GNC),straw N concentration(SNC),grain yield(GY),grain N accumulation(GNA),shoot total N accumulation(STN)and N harvest index(NHI))was performed based on SNPs in 46 NRT2 genes using a panel composed of 286 wheat cultivars.CGAS identified TaNRT2.1-6B as an elite NRT gene that is significantly associated with four(NHI,SNC,GNA and GY)of the six NUE-related traits simultaneously.TaNRT2.1-6B is located on the plasma membrane and acts as a dual-affinity NRT.The overexpression of TaNRT2.1-6B increased the N influx and root growth of wheat,whereas gene silence lines resulted in the opposite effects.The overexpression of TaNRT2.1-6B also improved GY and N accumulation of wheat under either limited or sufficient N conditions.The data provide the TaNRT2.1-6B gene and the two associated SNP markers as promising powerful tools for breeding wheat cultivars with high N uptake ability and NUE. 展开更多
关键词 Candidate gene association study WHEAT TaNRT2.1-6B Dual-affinity transporter Nitrogen use efficiency
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Aeroelastic modeling of wind loading on a cable-net supported glass wall 被引量:1
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作者 Zhifu Gu Letian Yang Yan Li Bin Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第3期409-415,共7页
Wind loading study on a cable-net supported glass wall is conducted by means of wind tunnel tests. An equiva- lent aeroelastic model is designed and constructed. Response of displacements of the wall is measured and a... Wind loading study on a cable-net supported glass wall is conducted by means of wind tunnel tests. An equiva- lent aeroelastic model is designed and constructed. Response of displacements of the wall is measured and analyzed. In order to design a glass wall under wind loading, the "wind- vibration factor" is estimated and discussed. In fact, the mech- anism of wind acting on the wall is commonly known not only as positive pressure, but also as negative pressure caused by the flow separation on the corners of the building. Due to the diffidence in the mechanism of wind acting, two typi- cal response cases are classified. The results show that the dynamic response of the structure caused by the negative pressure is stronger than that of the positive pressure case. To determine the aerodynamic wind loading on a flexible part of structure on a building, wind tunnel study may be useful and play an important role. 展开更多
关键词 Wind tunnel study Cable-net supported glasswall - Wind-vibration factor Aeroelastic model
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Deficiency of transmembrane AMPA receptor regulatory protein γ-8 leads to attention-deficit hyperactivity disorder-like behavior in mice
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作者 Wan-Jun Bai Xing-Guang Luo +13 位作者 Bao-Hua Jin Kang-Sheng Zhu Wen-Yan Guo Xiao-Que Zhu Xia Qin Zu-Xiao Yang Jiao-Jiao Zhao Si-Ruan Chen Ri Wang Jie Hao Fei Wang Yun Stone Shi De-Zhi Kong Wei Zhang 《Zoological Research》 SCIE CAS CSCD 2022年第5期851-870,共20页
Attention-deficit hyperactivity disorder(ADHD) is a neurodevelopmental disorder prevalent in schoolage children. At present, however, its etiologies and risk factors are unknown. Transmembrane α-amino-3-hydroxy-5-met... Attention-deficit hyperactivity disorder(ADHD) is a neurodevelopmental disorder prevalent in schoolage children. At present, however, its etiologies and risk factors are unknown. Transmembrane α-amino-3-hydroxy-5-methyl-4-isoxazolepropionicacid(AMPA) receptor regulatory protein γ-8(TARP γ-8,also known as calcium voltage-gated channel auxiliary subunit gamma 8(CACNG8)) is an auxiliary AMPA receptor(AMPAR) subunit. Here, we report an association between TARP γ-8 and ADHD,whereby adolescent TARP γ-8 knockout(KO) mice exhibitedADHD-likebehaviors,including hyperactivity, impulsivity, anxiety, impaired cognition,and memory deficits. Human single-nucleotide polymorphism(SNP) analysis also revealed strong associations between intronic alleles in CACNG8genes and ADHD susceptibility. In addition,synaptosomal proteomic analysis revealed dysfunction of the AMPA glutamate receptor complex in the hippocampi of TARP γ-8 KO mice.Proteomic analysis also revealed dysregulation of dopaminergic and glutamatergic transmissions in the prefrontal cortices of TARP γ-8 KO mice.Methylphenidate(MPH), which is commonly used to treat ADHD, significantly rescued the major behavioral deficits and abnormal synaptosomal proteins in TARP γ-8 KO mice. Notably, MPH significantly reversed the up-regulation of Grik2 and Slc6a3 in the prefrontal cortex. MPH also significantly improved synaptic AMPAR complex function by up-regulating other AMPAR auxiliary proteins in hippocampal synaptosomes. Taken together, our results suggest that TARP γ-8 is involved in the development of ADHD in humans.This study provides a useful alternative animal model with ADHD-like phenotypes related to TARP γ-8deficiency, which has great potential for the development of new therapies. 展开更多
关键词 Attention-deficit hyperactivity disorder TARPγ-8 METHYLPHENIDATE PROTEOMICS Phenome-wide association study
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Behavior of Cl^- Ions in Ag(SO_3)_2^(3-) Solution
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作者 王学文 胡建辉 《Rare Metals》 SCIE EI CAS CSCD 1997年第4期30-33,共4页
l- ions behavior in Ag(SO_3)3-2 solution was studied. The mechanism of Ag particles formation in the solution was discussed, and factors affecting its formation were investigated.
关键词 Ag(SO3)3-2 solution Cl- ions Behavior study
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Synthesis, Structure and Quantum Mechanical Calculations of Methyl 2-(5-((Quinolin-8-yloxy)-methyl)-1,3,4-oxadiazol-2-ylthio)-acetate
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作者 AAMER SAEED FOUZIA PERVEEN +2 位作者 NAEEM ABBAS SIDRA JAMAL ULRICH FL?RKE 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第6期858-870,共13页
The title compound was synthesized by the base catalyzed reaction of 5-((quinolin- 8-yloxy)methyl)-1,3,4-oxadiazole-2(3H)-thione with methyl chloroacetate. The structure was supported by the spectroscopic data a... The title compound was synthesized by the base catalyzed reaction of 5-((quinolin- 8-yloxy)methyl)-1,3,4-oxadiazole-2(3H)-thione with methyl chloroacetate. The structure was supported by the spectroscopic data and unambiguously confirmed by single-crystal X-ray diffraction studies. It crystallizes from a methanol solution in the triclinic space group Pi with unit cell dimensions a = 7.4509(9), b = 10.2389(12), c = 12.2299(15)A, a = 74.771(2), β = 77.956(2), 7 = 69.263(2)°, V = 834.98(17) A3 and Z = 2. In order to gain some valuable insights into the molecular structure, the quantum mechanical calculations were performed using both HF and time-dependent density functional theory at the B3LYP/6-31G(d,p) level. The molecular geometry from X-ray determination of the title compound in the ground state has been compared using the Hartree-Fock (HF) and density functional theory (DFT) with the 6-31G(d) basis set. The calculated results show that the DFT and HF can well reproduce the structure of the title compound. The energetic behavior of the title compound was examined using the B3LYP method with the 6-31G(d) basis set. The harmonic vibrational frequencies calculated have been compared with the experimental FTIR and FT-Raman spectra. The restricted Hartree-Fock and density functional theory-based nuclear magnetic resonance (NMR) calculation procedure was also performed, and it was used for assigning the 13C and 1H NMR chemical shifts of the title compound. Moreover, molecular electrostatic potential and thermodynamic parameters of the title compound were investigated by theoretical calculations. 展开更多
关键词 methyl 2-(5-((quinolin-8-yloxy)methyl)-1 3 4-oxadiazol-2-ylthio)acetate CRYSTALSTRUCTURE CONFORMER quantum chemical calculations vibrational studies
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RADICAL POLYMERIZATION OF N, N-DI(2-2'-METHYL-ACRYLOYLOXY-PROPYL)-PARA-TOLUIDINE FUNCTIONAL MONOMER
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作者 丘坤元 傅杰 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1989年第3期258-265,共8页
Functional monomer (MP)_2PT having tertiary aromatic amino group was systhesized from the reaction of N, N-di (2-hydroxypropyl)-p-toluidine with 2-methyl acryloyl chloride. In the presence of organic peroxide, the rad... Functional monomer (MP)_2PT having tertiary aromatic amino group was systhesized from the reaction of N, N-di (2-hydroxypropyl)-p-toluidine with 2-methyl acryloyl chloride. In the presence of organic peroxide, the radical polymerization of (MP)_2PT in toluene took place. The kinetics of (MP)_2PT polymerization and the ESR spectra of LPO-(MP)2PT-MNP systems were determined respectively. 展开更多
关键词 Functional monomer N N-di(2-2′-methylacryloyloxy-propyl )-p-toluidine Synthesis Radical polymerization Kinetics of polymerization ESR study on the radical intermediates.
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Synthesis,Crystal Structure and Characterization of a New Mixed-valence Cu(Ⅰ)/Cu(Ⅱ) Complex [Cu(bipy)(Me_2dtc)CuI_2]_n
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作者 范乐庆 吴季怀 +1 位作者 黄昀昉 林建明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第3期340-345,共6页
A new one-dimensional mixed-valence Cu(Ⅰ)/Cu(Ⅱ) complex [Cu(bipy)(Me2dtc)CuI2]n 1 (bipy = 2,2′-bipyridine and Me2dtc = N,N-dimethyldithiocarbamate) has been synthesized under solution condition, and chara... A new one-dimensional mixed-valence Cu(Ⅰ)/Cu(Ⅱ) complex [Cu(bipy)(Me2dtc)CuI2]n 1 (bipy = 2,2′-bipyridine and Me2dtc = N,N-dimethyldithiocarbamate) has been synthesized under solution condition, and characterized by elemental analysis, IR spectrum, single-crystal X-ray diffraction and magnetic property. The crystal belongs to the tetragonal system, space group P4122 with a = b = 11.6504(16), c = 13.466(3) A, V = 1827.8(5) A^3, Z = 4, Dc = 2.389 g/cm^3, Mr = 657.27, λ(MoKa) = 0.71073 , μ = 5.931 mm·1, F(000) = 1236, the final R = 0.0483 and wR = 0.1245. A total of 2102 unique reflections were collected, of which 2009 with I 〉 2σ(I) were observed. 1 consists of polymeric [Cu^II2]nn^- anions and [Cu^II(bipy)(Me2dtc)]^+ cations. It is interesting that the cations of 1 interact through π-π stacking interactions after rotating 90° to form one-dimensional chains parallel to the anion chains. The magnetic study indicates antiferromagnetic behavior for this complex. 展开更多
关键词 Cu(I)/Cu(II) N N-dimethyldithiocarbamate 2 2'-bipyridine crystal structure π-π packing interactions magnetic study
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Glyphosate-Residues in Roundup-Ready Soybean Impair Daphnia magna Life-Cycle
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作者 Marek Cuhra Terje Traavik +3 位作者 Mickael Dando Raul Primicerio Daniel Ferreira Holderbaum Thomas Bohn 《Journal of Agricultural Chemistry and Environment》 2015年第1期24-36,共13页
Herbicide tolerant plants such as Roundup-Ready soybean contain residues of glyphosate herbicide. These residues are considered safe and previous animal-feeding-studies have failed to find negative effects related to ... Herbicide tolerant plants such as Roundup-Ready soybean contain residues of glyphosate herbicide. These residues are considered safe and previous animal-feeding-studies have failed to find negative effects related to such chemical residues. The present study tests 8 experimental soy- meal diets as feed in groups (each containing 20 individuals) of test-animals (D. magna). The diets have different levels of glyphosate residues and we show that animal growth, reproductive maturity and number of offspring are correlated with these chemicals. The tested soybeans are from ordinary agriculture in Iowa USA and the residues are below the regulatory limits. Despite this, clear negative effects are seen in life-long feeding. The work enhances the need for including analysis of herbicide residues in future assessment of GMO. 展开更多
关键词 Transgenic GTS 40-3-2 Roundup-Ready Soybean Glyphosate Residues Life-Long Animal Feeding study GMO Risk-Assessment Herbicide-Tolerant Cultivar Quality Aquatic Invertebrate Ecotoxicology
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矿产资源概略研究、预可行性研究、可行性研究区别探讨 被引量:3
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作者 张亮 冯安生 +1 位作者 郭保健 刘磊 《中国矿业》 北大核心 2020年第3期18-23,共6页
矿产资源在进行勘查、开发过程中,为保证矿业项目的合理运行,需要进行技术经济可行性评价,可行性评价分为概略研究、预可行性研究和可行性研究三个阶段,三个阶段研究深度不断加深。概略研究侧重于机会研究,各类参数通常以同类型相似矿... 矿产资源在进行勘查、开发过程中,为保证矿业项目的合理运行,需要进行技术经济可行性评价,可行性评价分为概略研究、预可行性研究和可行性研究三个阶段,三个阶段研究深度不断加深。概略研究侧重于机会研究,各类参数通常以同类型相似矿山类比得出,其经济评价以静态评价为主,误差范围通常为±50%左右;预可行性研究侧重于可操作性研究,各类参数是在初步试验基础上结合矿山假定的生产建设方案设定的,经济评价是基于矿山周期内年均产量、单位成本花费和总的数量进行评价,估算误差通常在30%以内;可行性研究侧重于项目实际生产经营时的盈利性研究,各类估算参数是模拟实际生产运营条件下得出的,经济评价为详细的动态评价,并进行相应敏感性分析,具有很强的时效性,估算误差通常在±15%以内。 展开更多
关键词 技术经济评价 概略研究 预可行性研究 可行性研究
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一种耦合燃气轮机的富氧燃烧系统技术经济性能分析 被引量:3
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作者 邱丽霞 郝艳红 《机械工程学报》 EI CAS CSCD 北大核心 2016年第18期153-158,共6页
提出一种燃气轮机与富氧燃烧耦合的动力系统,该系统利用烟气排烟余热和锅炉内设高温受热面加热压缩空气,使其推动燃气轮机涡轮做功,用燃气轮机的压气机替代空分系统的压缩机,实现空分系统和动力系统耦合,同时燃气轮机也是烟气CO2压缩机... 提出一种燃气轮机与富氧燃烧耦合的动力系统,该系统利用烟气排烟余热和锅炉内设高温受热面加热压缩空气,使其推动燃气轮机涡轮做功,用燃气轮机的压气机替代空分系统的压缩机,实现空分系统和动力系统耦合,同时燃气轮机也是烟气CO2压缩机的原动机。对新系统进行热力学与经济性分析,对应计算系统净供电效率和供电成本。结果显示当工质在锅炉高温受热面中的吸热量占燃气轮机热耗的比β为0.8、燃气轮机效率ηgt为0.32时,新型耦合系统净效率可比常规富氧燃烧系统增加4.2%,供电成本降低0.044元/(k W·h)。 展开更多
关键词 燃气轮机 富氧燃烧 空分 净效率 技术经济
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